Performance Complies with ANSI A156.4, Grade 1, 2 million cycles. UL/ULC listed up to 3 hours fire rated, Chassis/Closer Cast aluminum, Handing Non-handed, Mounting Tri-Pack regular, top jamb and parallel arm applications. Main Arm Forged steel, accommodates reveals up to 3-1/4, adjustable extension arm, Spring Power Adjustable sizes 1 - 4, Fasteners Metal screws included for hollow metal and aluminum mounting applications. Wood screws included for wood door mounting applications. Thru-bolts optional. Hole Pattern Fits same hole pattern as Norton 1600 or Yale 50 Series